1. Field of the Invention
The present invention relates to a straddle-type vehicle, and more particularly, to a vibration isolating structure of a fuel tank of a straddle-type vehicle.
2. Description of Related Art
Straddle-type vehicles may include a fuel tank attached to a body frame below a seat. Such a vehicle is disclosed, for example, in JP-A-2006-88892. If fuel is supplied to the engine by fuel injection, a fuel pump is attached to the fuel tank to control the supply of fuel to the engine. JP-A-2005-247022 discloses a straddle-type vehicle in which a fuel pump is attached to the fuel tank.
Fuel tanks are typically not too thick in order to maintain a lightweight structure. In addition, the top surface of the fuel tank typically has a fuel filler hole and, if fuel is supplied by fuel injection, a fuel pump mounting hole for mounting the fuel pump. Therefore, the top of the fuel tank is not very rigid. Vibration of the engine is transmitted to the fuel tank through the body frame and causes the fuel pump to vibrate in the fuel tank since the top of the fuel tank is not very rigid. Excessive vibration of the fuel pump may cause problems in refueling.
The inventor has investigated methods for damping this vibration. For example, the inventor tried pressing down the vibrating portion of the top of the fuel tank from above with a load from the seat, with an elastic member such as rubber attached to a part adjacent to the seat. However, the vibration was not damped sufficiently only by pressing down the vibrating portion. Therefore, further improvement is required.